The invention relates to optical beam scanning devices, and more particularly to a scanning device for producing a plurality of scan lines using one or more rotating mirrors.
Optical beam scanning devices, particularly those in laser bar code readers, are in wide use. A variety of types of scanning mechanisms exist. These include resonant reciprocating scanners in which spring-loaded vibration or reciprocation causes a mirror to reciprocate and thus reflect a laser beam to produce a scan line, and other forms of scanning mechanisms involving rotational elements for effecting position and orientation changes in one or a plurality of mirror surfaces to generate the desired scan pattern. Typical slot scanners used in retail stores, for example, generating non-parallel pairs of scan lines, utilizing rotating components for manipulating mirrors. In such scanners, generally multiple pairs of parallel lines are produced from a single laser beam.
In general, the existing systems for use in generating a plurality of scan lines, particularly involving non-parallel scan lines, are relatively complex in structure and adjustment. Therefore, there has been a need for a simple scanning mechanism having relatively few parts, which is dependable and versatile for producing any of a variety of desired scanning patterns.